Sorting machine



Aug. 8, 1961 Filed Jan. 27. 1956 J. M. CUNNINGHAM ETAL SORTING MACHINE 2 Sheets-Sheet 1 JAMES M. CUNNINGHAM CARL D. HICKS ATTORNEY Aug- 8, 1961 J. M. CUNNINGHAM ETAL 2,995,240

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INVENTOR. JAMES M. CUNNINGHAM CARL D. HICKS BY ATTORNEY United States Patent C 2,995,240 SORTING MACHINE James M. Cunningham, Endicott, and Carl D. Hicks,

Vestal, N .Y., assgnors to International Business Machines Corporation, New York, N.Y., a corporation of New York Filed Jan. 27, 1956, Ser. No. 561,815 7 Claims. (Cl. 209-110) This invention relates to record controlled distributing machines and more particularly to improved means for separating properly registered records from improperly registered records.

In an elapsed time recording machine such as that disclosed in U.S. Patent No. 2,970,878 of James M. Cunningham, attendance record cards are punched in a predetermined location lon each occasion that a card is inserted in the machine for recording. The absence of a punching in such a location renders a card incorrect or improperly registered. Through means of the present invention, a stack of attendance cards is separated into two groups, one containing properly registered cards and the other improperly registered cards.

Accordingly, the principal object of this invention is to provide an improved means to sort properly registered cards and improperly registered cards into two separate groups from a stack containing such cards commingled.

Briefly, the sorting machine of the present invention sorts attendance record cards having perforations in successive perforate index positions in a plurality of columns representing registration data and line positioning holes and successive imperforate index positions in the same columns. The presence of both registration and line positioning perforations is required in each perforate index position and the absence of any perforation is required in the imperforate index positions of a correct card. The correct and incorrect cards are directed into separate pockets by the sorting means. Circuit means is provided for controlling the sorting means, the operation of which is determined by a control device. Means responsive to the sensing of a line positioning perforation in a column of an imperforate index position actuates the control device to control operation of the circuit means and means is effective to actuate the device when a plurality of registration perforations is not sensed in a perforate index position, whereby the operation of the circuit means is controlled. The circuit means in turn controls the sorting means and the incorrect card is directed into a certain pocket.

Other objects fof the invention will be pointed out in the following description and claims and illustrated in the accompanying drawings, which disclose, by way of examples, the principle of the invention and the best mode, which has been contemplated, of applying that principle.

In the drawings:

FIG. 1 shows a circuit diagram of the preferred form of the present invention illustrated in connection with the associated mechanical devices of a sorting machine.

FIG. 2 is a view showing a typical attendance record card which has been properly processed through an elapsed time recorder for six working days.

FIG. 3 is a timing chart showing the timing desirable to close certain electrical contacts and circuits for embodiment as shown in FIG. 1.

FIG. 4 is a circuit diagram of another embodiment of this invention showing the circuit connections to the sorting devices illustrated in FIG. l.

FIG. 5 is a timing chart showing the timing desirable to close certain electrical contacts and circuits for the embodiment of FIG. 4.

For illustrative purposes, the invention is shown as apf' ice plied to a sorting machine of the electrically controlled type. This machine is well known in the art and its various details of construction and manner 'of operation are disclosed in Patent No. 2,615,569, issued October 28, 1952 to C. D. Lake et al. Since the aforesaid patent describes the machine in detail, it is unnecessary to give l more than a very brief description of the general features herein, except to point out wherein the improvements of the present invention are applied.

A group of record cards which consists of the usual IBM cards designated 10 (FIG. l) is placed in a magazine and removed one at a time from the bottom of the magazine by means of a picker knife 11. The cards are advanced between rollers 12, which in turn feed the cards between a series of four brushes designated 13, 14, 15 and 16 and a contact roll 18, in a well known manner.

The index point positions in the well known IBM card are shown in FIG. 2 to be differentially located from the edges of the card. The cards are fed face down with the 9 edge leading and after this leading edge passes the forementioned brushes, it passes between a table 19, forming an armature for a pair of sorting magnets 20, and a series of guide tongues 21 pressed lightly into contact with said table by the inherent spring tension of the tongues.

When a brush encounters a perforation during the passage of a card thereby, the leading edge of the card is located between two of the tongues 21, depending upon the differential location of the perforation. At this time, the brush makes contact with the rolle-r 18, closing an electrical circuit to energize the sorting magnets 20. The energization of the sorting magnets causes the table to be lowered, the tongues 21 to the left of the card moving downwardly therewith and the remaining tongues 21 being supported by the card, thus determining the particular pocket to which the card subsequently will be guided.

In the present embodiment of the invention, only two pockets are utilized and those cards having perfonations in predetermined index point positions in one or more columns are sorted into the pocket 60 and those cards without a perforation in any predetermined index point position in one or more of the columns are sorted into the l2 pocket 61.

In this embodiment, the energization of the sorting magnets 20 is delayed until the 12 index position on the card reaches the row of sensing brushes, whereupon the cards without a perforation in any predetermined index position are directed into the 12 pocket 61. The energization of magnets 20 is prevented when a card has perforations in the predetermined index positions and the card is passed under all of the tongues 21 into the pocket 60.

The present invention is primarily utilized in handling either attendance cards or job cards from an elapsed time recording machine of the type disclosed in the forementioned Patent No. 2,970,878 of James M. Cunningham. The cards are sorted into two groups, one group being properly registered cards and the other group being improperly registered cards.

'Ihe preferred card form for an elapsed time attendance record card is shown in FIG. 2. The card would normally be pre-punched with employee name, number, social security code number, etc., which are interpreted at the top of the card. The punchings 23 represent the setting of the time recorder when the card is presented for In recording and are punched in columns 4 to 15. The start time and date are printed in columns 4f] to 59 (not shown). The punching of a registration hole 24 is made at this time in column 16 and a line positioning hole 25 is punched in column 18. When the card is presented for Out recording, the punchings 26 representing Vthe setting of the time recorder are punched in columns 23 to 34 and the punching of the registration hole 27 and the line positioning hole 28 are made in columns 35 and 37. It is to be understood that the card shown and described is merely an example of one` form of card that may be used in connection with the present sorting device and that other card forms could also be utilized.

The improperly registered cards can be of two classes in one of which the employee fails to ring in or ring out and no line positioning hole is punched in column 18 or column 37 nor is a registration hole punched in columns 16 and 35. In the other class of improper cards, the employee presents the card to the recorder at improper time periods and registration hole columns 16 or 35 remain unpunched but a line positioning hole is punched in columns 18 or 37. A proper ring in or ring out causes registration columns 16 or 35 and line positioning columns 18 or 37 to be punched.

Each index position or row of a card indicates a particular portion of the work week and any possible length of work week including a fractional day can be registered with a maximum of twelve registrations possible.

Circuit diagram and operation In the embodiment shown in FIG. 1, a dial switch 30 having twelve conductive segments 29 is set by the machine operator at the index position which indicates the dividing line for the length of the Work week. The dividing index position and all subsequent positions require four holes in columns 16, 18, 35 and 37, respectively, to be a properly registered or correct card. The other index positions must not contain any holes in these columns to be a properly registered card.

A suitable source of current supply provides voltages so that lines 31, 32 and 33 are at 0, +140 and 40, respectively. These voltage values are given only by way of example, it being understood that any suitable voltage values may be employed. A switch 35 is moved to the On position to place the various electrical devices in circuit connection. The cards are fed to the row of sensing brushes 13-16 for the columns of the card 16, 18, 35 and 37 with the 9 edge leading in a well known manner. A set of electrical terminals 62-68 is provided in the machine so that the wires leading to the sorting magnets and sensing brushes can be connected to other control devices as explained hereinafter.

For purposes of explanation, let it be assumed that the switch 30 is set at the 6 index position (as shown). As the 9, 8 and 7 index positions are fed past the line positioning brushes 14 and 16, any hole in columns 18 and 37 will fire a cold cathode gas tube 36 by providing a positive pulse to the starter anode 36a. A commutator 37 is of a conventional type and includes twelve conductive segments 39 which cooperate with a brush 40 and metallic strips 41 and 42 which in turn cooperate with brushes 43 and 44 respectively. The strips are electrically connected to each other and to the Contact segments 39. The commutator is synchronized with the speed of the passage of cards through the machine and moves its segments 39 past the brush 40 in step with the passage of the index positions on the card past the sensing brushes 13-16. As a result, each index position of the card corresponds to a predetermined contact segment 39. The positive pulse to the starter anode of tube 36 is provided through this sort commutator 37 by the following connection: From line 32, through commutator brush 44, strip 42, segment 39, brush 40, relay contacts R10d (normally closed), terminal 64, common contact brush 38, Contact roll 18, line positioning brushes 14 and/or 16, terminals 66 and/or 68, relay contacts R10a (normal), resistor 101 to starter anode 36a of tube 36 and in parallel through a resistor 102 to the -40 volt line 33. When tube 36 fires, a circuit is completed from the anode 36b through the brushes 43 and 44 of the sort commutator 37 to line 32 and to the +140 volt supply to hold the tube 36 conductive.

The cathode of the tube 36 is connected to the -40 volt supply line 33 through a resistor 103 which supplies the proper D.C. bias to the control grids of vacuum tubes 46. The starter anode 36a is normally biased negatively by means of the -40 volt supply applied through resistors 102 and 101. When the positive voltage pulse is applied by means of Ithe `above traced circuit, lthe tube 36 conducts and the cathode voltage rises and places `a positive voltage on the grids of vacuum tubes 46 to render them conductive. A circuit is thus completed to the sorting magnets 20 through tubes 46 as follows: From line 32, through terminal 62, sorting magnets 20, terminal 63, tubes 46 (now conductive), resistor R1 to line 31. However, the current is limited by the resistance value of R1 so that the magnets 20 are not energized at this time. A commutator 47 is located in parallel with the resistor R1 and from FIG. 3 it is seen that the commutator is timed to close the parallel circuit as the 12 index position on the card passes the row of brushes 13-16. The resistor R1 is thus shunted and full current through `47 is permitted to reach the sorting magnets to energize them `at l2 time. Any improperly registered cards having holes in the 9, 8 or 7 index positions are thus sent to the 12 pocket 61.

Referring again to the diagram of FIG. l, it is seen that an emitter E1, which is a pulse distributor, having twelve conductive segments 49 is connected by wires 50 to the segments 29 of the dial switch 30. Emitter E1 is synchronized with the passage of the card past the row of brushes 13-16 to electrically connect this emitter and the i dial switch between the sensing of each index position (FIG. 3). Shortly after 7 time and prior to 6 time, the emitter will match the setting on the switch 30 and a positive pulse is sent to the control grid 52a of a thyratron tube 52 through switch 35. When the grid 52a is thus raised to 140 v. the tube 52 is red to complete a circuit which picks up a relay R10 through a commutator 53 as follows: From line 32, through commutator 53 (now closed), coil of relay R10, tube 52 (now conductive). to line 31. The energization of relay R10 closes its contacts b, c, e, opens its d contacts and transfers its n contacts to condition circuits for detecting the absence of a hole in either registration columns 16 and 35 in index position 6 or any index position subsequent to the 6 index position.

The card is not tested for the line positioning holes in the dividing index position and subsequent index positions because registration holes only exist withan accompanying line positioning hole in these index positions. If a hole exists in both registration columns of the 6 position, the sensing of these holes by brushes 13 and 15 does not cause the tube 36 to fire. Instead, a circuit is completed from line 32, through relay contacts R (now closed), resistances R2 `and R3, terminals 65 and 67, brushes 13 and 15, contract roll 18, common brush 38, terminal 64, relay contacts R10e to line 33. This is in effect a short circuit on any other parallel resistance circuits and the current has no tendency to ow through the rectitiers 55 and 56. Let it be assumed that a hole is not present in column 35 of the 5 index position. When this position is sensed by the brushes 13 and 15, a positive pulse is placed on the starter anode 36a of tube 36 to tire this tube. Since there is no hole in column 35, the current will pass through rectifier 56 to provide the positive pulse by a connection as follows: From linc 32, through relay contacts RlOc (now closed), resistor R3, rectifier 56, commutator 58, relay contacts R10/J (now closed), relay contacts R10a (transferred), to the starter anode 36a. Commutator 58 is Ithe registration test conimutator which is closed shortly after 9 time and remains closed until after 12 time. Current will pass through the brush 13 for column 16 as before. Where a registration hole is absent from both columns 16 and 35, a full positive pulse is impressed on the starter anode of tube 36 through both resistors R2, R3 and both rectiers 55, 56. The positive pulse to anode 36a is only effective to re the tube 36 when emitter E2 is open so that the -40 v. bias is taken off the anode. In

gegaan) FIG. 3 it is seen that the bias is removed shortly after the sensing of each index position. When tube 36 becomes conductive, a circuit .is completed through the sorting magnets 20 las previously described and the improperly registered card is directed into the 12 pocket upon the closing of commutator 47 -at 12 time.

In the case where there are no holes in columns I16, 18 and 35, 37 in the 9, 8 and 7 index positions and all pairs of holes exist in these columns in index positions 6 through l2, the card is properly registered and the tube 36 is not made conductive. This prevents energization of the sorting magnets -20 at the 12 time under control of the commutator 47 andthe card is directed into the pocket 60.

Registration errors at the 12 index position cause the immediate energization of sorting magnets 20 when emitter E2 opens since commutator 47 is already closed.

In summarizing the above description, it can be seen that there is:

(l) A card distributor which includes the guide blades (2) A card transport which includes driving wheels 12 for moving the cards to a particular pocket (3) A sensing circuit for controlling the card distributor in response to the presence or absence 0f perforations which includes:

a. The comparing bridge R2, R3; 55, 56 b. Gas tube 36 c. Tubes 46 d. Brushes 13-16 Commutator 42 (4) Selective switching means for controlling the sensing means which includes:

a. Emitter El b. Switch 30 c. Relay R10 which is a selecting relay -The breakdown of the circuit of FIG. 1 illustrates the operation of the machine quite clearly as one in which the sensing of records is achieved selectively by means of a switching arrangement which controls the sensing to divide the sensing into two distinct operations of which the first is to detect holes in an irnperforate position and the second to detect no holes in a perforate position.

Y In the embodiment of FIG. 4, the circuit connections to terminals 62-68 inclusive are shown. These terminals are connected to any suitable sorting machine such as shown in FIG. 1. The sorting circuit of FIG. 4 operates to perform the same functions as the sorting circuit shown in FIG. l, but directs cards which are in the correct group into the pocket 61 as shown in FIG.1 and the cards which are incorrect into pocket 60. 'I'rhis represents a reversal over FIG. 1 in the sorting of cards into the various pockets.

A dial switch 80 having twelve conductive segments 81 is set by the machine operator at the index position which indicates the dividing line for the length of the work week. The dividing index position and all subsequent positions require four holes in columns 16, .18, '35 and 37 respectively, to be a properly registered card. The other index positions must not contain any holes in lthese columns to be a properly registered card.

Current is supplied by lines 82 and 83. A switch 84 is moved .to the On position to place the various electrical devices in circuit connection. For purposes of illustration, let it be assumed that the switch 80 is set at the 6 index position. As the 9, 8 and 7 index positions are fed past the line positioning brushes (FIG. l), any hole in columns 18 and 37 will energize an error relay R12 through a commutator 85 which includes twelve conductive segments 86, brushes 87, 88 and a conductive strip 89. The segments 86 are each electrically connected to the strip 89. The commutator is synchronized with the speed of the passage of cards through the machine and moves its segments 86 past the brush 87 in step with the passage of index positions on the card past the row of brushes. As a result, each index position of the card corresponds to a predetermined contact segment 86. The relay R12 is energized by a circuit as follows: =Frorn line 82 through commutator brush 87, segment 86 in the 9, 8 or 7 position, strip 89, brush 88, switch 84, emitter E2, relay contacts R14d (normal), to terminal 64 and through either of the line positioning brushes to terminals 66 or 68, relay contacts R14b (normal), relay contacts R16b (normally closed), pickup coil of relay R12 to line 83. The energization of relay R12 closes its a contacts to complete a circuit through its holding coil R12H as follows: From line 82 through commutator 90, relay contacts R12a (now closed), hold coil R12H of relay R12 to line 83. When relay R12 is energized its d contacts are closed to short the sorting magnets 20 so that these magnets cannot be energized at l2 time, thus sending the improperly registered card to the pocket 60.

An emitter E1 is provided with twelve conductive segments 91 and is connected by wires 92 to the segments 81 of the dial switch 8l). Between the 7 and 6 times the emitter yEl will match the setting on the switch and pick up relay R14. lRelay R14 is picked up by a circuit from the line 82 through the commutator 90, through the emitter E1 with its moving contact standing ybetween the 7 and 6 through the associated Wire 92 through the stationary contacts of dial switch 80 through a resistance network to relay R14 and to the line 83. The energization of relay R14 closes its a contacts to form a holding circuit for this relay as follows: From line 82, through commutator 90, relay contacts R14a (now closed), coil of relay R14 to line 83. This holding circuit endures until the commutator opens at the end of a card cycle. The energization of relay R14 also closes its "c" contacts and transfers its "b and "d contacts to condition circuits for detecting the labsence of a hole in either registration columns 16 and 35 in the 6 index position and any index position subsequent to the 6 index position.

The card is no-t tested for the line positioning holes in the ydividing index position and subsequent index positions because registration holes only exist with an accompanying line positioning hole in these index positions. If a hole exists in both registration columns of the 6 position, the sensi-ng of these holes by the registration brushes does not cause the error relay R12 to be energized. Instead, a circuit is completed from line 82, through commutator 85, switch 84, emitter E2, relay contacts R14d (transferred), relay contacts R14b (transferred), to terminal 65, then through the registration brush 13 for column 16, contact roll 18 and brush 15 for column 35 to terminal 67 (FIG. 1), and relay contacts R166` (normal), relay contacts R140 (now closed), to line 83. This circuit causes the pick-up coil of the error relay R12 to be shunted by the registration brushes so that insufficient current will be drawn through R12 to operate this relay. It is thus apparent that a pulse is supplied at each index position but does not energize the error relay R12 on a properly registered card because both registration brushes sense a hole in the card.

Let it be assumed that a hole is not present in column 35 of the 5 index position. When this position is sensed by the registration brushes, the error relay :R12 is energized lthrough the following circuit: From line 82, through commutator 85, switch 84, emitter E2, relay contacts R14d (transferred), relay contacts R16b, (normally closed), coil of error relay R12 to line 83. Since a hole is not sensed in column 35 by brush 15, the error relay coil is not shorted and becomes energized. The energization of relay R12 causes the improperly registered card to be sent to the reject pocket as previously described.

In the instance of a properly registered card, that is a card containing no perforations in the imperforate area and containing al1 necessary perforations in the registrations columns in the perforate area, emitter E1 closes just prior to 12 time and a relay R16 is energized through the 12 segment 81 of the dial switch Si). This relay then closes its a contacts, opens its b contacts and transfers its c contacts. The opening of these "b" contacts prevents the error relay R12 from being energized at 12 time, whereupon a circuit is completed through the sorting magnets (FIG. 1) as follows: From line S2, through commutator 85, switch S4, emitter E2, relay contacts R14d (transferred), relay contacts R14b (transferred) to terminal 65, through the two registration brushes 13, and the contact roll to terminal 67, relay contacts R160 (transferred), brush relay R18, to terminal 63 and through the sorting magnets to terminal 62 and line 83. The energization of the sorting magnets at l2 time causes the sensed card to be directed into the 12 pocket. A holding circuit for the sorting magnets is established through the coil of relay R13 and the relay contacts R18a, which are closed upon energization of the relay R18. Therefore, if there are no holes in columns 16, 18 and 35, 37 in the 9, 8 and 7 index positions and all pairs of holes exist in these columns in index positions 6 through 12, the card is properly registered and will be sorted into the 12 pocket.

If the dial switch 80 is set at the 12 segment, the relays R14 and R16 are energized simultaneously just prior to l2 time to detect the absence of holes in columns 16 or 35 in the manner described above. In the instance where a card is correct in all index positions except the l2 position, relay R16 is energized at l2 time and a test is made for both holes in columns 16 and 35. If either or both holes are missing then no circuit is completed to pick up relay R18 and the card is directed to the reject pocket.

The sensing circuit of FIG. 4 includes:

a. The sensing relay R12 b. Brushes c. Commutator 85 while the selective switching means would include:

a. The emitter E1 b. The switch 80 c. The relay R14 While there have been shown and described and pointed out the fundamental novel features of the invention as applied to a preferred embodiment, it will be understood that various omissions and substitutions and changes in the form and details of the device illustrated and in its operation may be made by those skilled in the art, without departing from the spirit of the invention. It is the intention, therefore, to be limited only as indicated by the scope of the following claims.

What is claimed is:

l. In a machine having a plurality of card receiving pockets, a card distributor including guide blades for selectively guiding cards to selected pockets, a sensing circuit selectively operable to detect the presence or absence of perforations in a selected plurality of columns for controlling said card distributor to sort cards containing perforations in a plurality of columns and at predetermined exclusive index positions into a common pocket and sorting all others into a reject pocket, a perforation sensing means included in said sensing circuit for each said column, a card transport for moving cards past said sensing means in a columnar direction and through said distributing means to a selected pocket, and selective switching means for operating said sensing circuit to detect perforations at index positions other than said predetermined index positions in a selected plurality of columns', whereby said card distributor is controlled to direct cards containing perforations in a plurality of columns at predetermined exclusive index positions into a common pocket.

2. The apparatus of claim 1 wherein said selective switching circuit includes a pulse distributor operable in synchronism with movement of the index positions of said card past said sensing means to sequentially transmit pulses to a plurality of output lines, a contact selectively movable to one of said output lines, and a selecting relay connected to said movable contact and oper ated when said movable contact and the pulse to that output line coincide and having a plurality of contact points in said sensing circuit wherein said sensing circuit is made responsive to two conditions as determined by the operated or unoperated condition of said relay.

3. The apparatus of claim 2 wherein said sensing circuit includes sorting magnets for moving said guide blades and a sensing relay connected in a closed series circuit with a closed contact point of said selective switch ing circuit and with a plurality of parallel connected sensing means when said selecting relay is unoperated to operate said sensing relay when a perforation is sensed and shunt said sorting magnets.

4. The apparatus of claim 3 wherein said sensing circuit includes a shunt circuit for said sensing relay for preventing the operation thereof including a series oonnection through sensing means in a selected plurality of columns and various contact points of said selection relay when said selection relay is operated whereby the absence of a perforation in a selected column opens said circuit and said sensing relay is operated to shunt said sorting magnets.

5. In a machine having a plurality of card receiving pockets for sorting record cards containing perforations in a plurality of columns and at predetermined exclusive index positions into ya common pocket and sorting all others into a reject pocket, a card distributor including guide blades for selectively guiding cards to selected pockets, a sensing circuit selectively operable to detect the presence or absence of perforations in a selected plurality of columns including a perforation sensing means for each said column operable to transmit a voltage upon detection of a perforation, a voltage responsive space discharge tube for controlling said card distributor, a bridge circuit responsive to a plurality of voltages applied thereto to generate a voltage output when said applied voltages are not of the same magnitude, a card transport for moving cards past said sensing means in a columnar direction and through said distributing means to a selected pocket and selective switching means for connecting said selected sensing means to said voltage responsive space discharge tube at index positions other than said predetermined index positions and for connecting said bridge circuit between selected sensing means and said voltage responsive tube at said predetermined index positions to operate said voltage responsive tube upon detection of perforations at index points other than those predetermined points and upon omission of perforations at said predetermined points to control said card distributor to direct cards into said reject pocket.

6. The apparatus of claim 5 wherein said selective switching circuit includes a pulse distributor operable in synchronism with movement of the index positions of said card past said sensing means to sequentially transmit pulses to a plurality of output lines, a contact selectively movable to one of said output lines, a selecting relay responsive to said movable contact and operated when said movable contact and the pulse to that output line coincide and having a plurality of contact points in said sensing circuit wherein said sensing circuit is made responsive to two conditions as determined by the operated or unoperated condition of said relay.

7. The apparatus of claim 6 wherein said sensing circuit includes sorting magnets for moving said guide blades and energization means for said sorting magnets operable upon operation of voltage responsive tube to energize said magnets.

References Cited in the file of this patent UNITED STATES PATENTS 2,615,568 Constance Oct. 28, 1952 UNITED STATES PATENT. @mice b CERTIFICATE GF CGRREQTEQN laten, Nm? QUQQSQZQO A Augue, 8. 1.961

James M., Cunningham et ela It is hereby certified that error appears n the above numbered pat ent requiring correction and that the Said Letters Patent ehould reed as corrected belowc Column 7g line 6% ailier sommes insert and for operating Seid sensing ciruiiyto eleteeJ wie absence of perforatione in seid predejcermined index positiene in a selected plurality of eolumne Signed and sealed this 9m dey O Jennery 1962.

(SEAL) Attest:

ERNEST "XL SWIDER DAVID L. LADD Attesting ffieer Commissioner of Patents 

